> A category consists of abstract functions (or morphisms, or “arrows”) that have an origin and destination (or domain and codomain, or “argument type” and “return type”).
I think perhaps Maths people need to seek more consensus on terminology.
I think perhaps Maths people need to seek more consensus on terminology.
All the other terms here (abstract functions, origin, destination, argument type, return type) appear to be the author's attempt to make the subject understandable to programmers.
In Graph Theory the terminology is Node and Vertex.
Arrow, Source and Target are from Category Theory.
In CT you usually are dealing with morphisms, but not always and that intuition can get in your way. For this reason, arrow is sometimes used instead to indicate something a little more abstract than morhism.
If only they could follow the example of programmers, who never have two different words for identical (or, worse, near-identical) concepts!
- Morphism (Domain, Codomain)
- Arrow (Source, Target)
The reason for the last one is that you may find "Arrows" that aren't functions. (Such as an order relationship in the Poset category)